Simplify the following expression: $p = \dfrac{1}{2k} + \dfrac{10}{7k}$
Solution: In order to add expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $2k$ and $7k$ $\lcm(2k, 7k) = 14k$ $ p = \dfrac{7}{7} \cdot \dfrac{1}{2k} + \dfrac{2}{2} \cdot \dfrac{10}{7k} $ $p = \dfrac{7}{14k} + \dfrac{20}{14k}$ $p = \dfrac{7 +20}{14k}$ $p = \dfrac{27}{14k}$